Anti-corrosion composition comprising at least one first compound and at least one second compound

ABSTRACT

An anti-corrosion composition includes a first compound including: a first polyisobutylene having an average relative molar mass ranging from about 30,000 to about 100,000 g/mole and a Staudinger index ranging from about 15-70 cm3/g, a first depolymerized butyl rubber with Brookfield viscosity at 66° C. ranging from about 400,000-2,000,000 mPa·s and an average molecular weight ranging from about 20,000-60,000, and combinations thereof. A second compound includes a second polyisobutylene having an average relative molar mass ranging from about 900,000-6,500,000 g/mole and a Staudinger index ranging from about 240-900 cm3/g, at least one second partly cross-linked butyl rubber with a Mooney viscosity at 127° C. ranging from about 65-100 MU. The anti-corrosion composition includes at least one first or at least one second polyisobutylene as well as at least one first or at least one second butyl rubber.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the U.S. national stage of PCT/EP2016/077763, filedNov. 15, 2016, which claims priority of DE 102015119790.1, filed Nov.16, 2015.

TECHNICAL FIELD

The present invention relates to an anti-corrosion compositioncomprising at least a first compound and at least a second compound andtheir use for protecting pipes and systems comprising pipes as well asother plants and installations, as well as to a method for achievingcorrosion protection, and to an at least single-layered wrapping tapecomprising the composition according to the invention.

BACKGROUND

Anti-corrosion compositions and anti-corrosion systems used for examplefor pipe plants such as pipelines, but also for other technical plants,are widely known from the prior art. EP 0 421 607 A1 for examplediscloses a tape wrap system for protecting tubular articles comprisingan innerwrap covering the surface of the article to be protected and anouterwrap placed over said innerwrap, said innerwrap comprising animpact-resistant layer carrying an adhesive layer on its inner surfaceand a layer on its outer surface, and said outerwrap comprising acarrying layer having a layer on at least one of its surfaces, saidinnerwrap and outerwrap including a heat fusable material, and said tapewrap system is applied to the tubular article in a way that saidouterwrap heat fuses together with said innerwrap when heated andthereafter cooled, thus forming a completely closed protective coating.The object of the tape wrap system disclosed above is to provide acontinuous, seamless, protective tape wrap system in order to improveresistability against destructive external forces. one of the adhesivelayers can for example be made of butyl rubber. As heat fusable materialfor example ethylene vinyl acetate, ethylene methyl acrylate andpolyethylene of low density are used. The problem of the tape wrapsystem disclosed in EP 0 421 607 A1 is in case of wrapped pipe systemsand technical plants of each kind especially at higher temperatures thecontact between for example the outer surface of a pipeline tube and theadhesive layer, for example of butyl rubber, which might loosen from theouter surface of the pipeline tube.

Corresponding problems do also occur, if anti-corrosion compositions arenot used in a tape format but for example as a spattling compound. Here,especially at high temperatures, a sufficient adhesion between thespattling compound and for example steel surfaces is not given either.The adhesion of materials is in particular characterized as peelstrength, also referred to as peel resistance and can be determinedaccording to DIN 112068 in the version of 1999-03. However, not only athigh temperatures, but often also at room temperatures (20° C. or 23°C.) the above-mentioned adhesion is improvable. Therefore, in prior art,an improved adhesion is often achieved by using a primer/adhesivecontaining solvents.

SUMMARY

The object of the present invention is therefore to provide ananti-corrosion composition which offers an improved adhesion on surfacesof each kind, for example pipes or systems comprising pipes includingpipelines, as well as other installations, and which preferablyfurthermore provides an improved mechanical strength.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

This object is achieved by an anti-corrosion composition comprising atleast a first compound selected from a group comprising at least a firstpolyisobutylene with an average relative molar mass M _(V) ranging fromabout 14,000 g/mole, preferred to about 30,000 g/mole, to about 150,000g/mole, preferred to about 100,000 g/mole and a Staudinger-Index J₀ranging from about 15 cm³/g to about 70 cm³/g and/or at least a firstdepolymerized butyl rubber with an apparent Brookfield viscosity at 66°C. according to DIN EN ISO 2555:2000-01ranging from about 400,000 mPa·sto about 2,000,000 mPa·s and an average molecular weight M_(w) rangingfrom about 20,000 to about 60,000, and at least a second compound,selected from a group comprising at least a second polyisobutylenehaving an average relative molar mass M_(V) ranging from about 900,000g/mole, preferred from about 950,000 g/mole, to about 7,500,000 g/mole,preferred to about 6,500.000 g/mole, and a Staudinger-Index J₀ rangingfrom about 240 cm³/g to about 900 cm³/g and/or at least a second partlycross-linked butyl rubber with a Mooney viscosity ML(1+3) at 127° C.ranging from about 65 MU to about 100 MU according to ISO 289:2005,wherein the anti-corrosion composition comprises at least one first orat least one second polyisobutylene as well as at least one first or atleast one second butyl rubber.

Formerly, the Staudinger-Index J₀ was also referred to as IntrinsicViscosity. It is calculated from the flow time at 20° C. through acapillary of an Ubbelohde viscometer according to the following formula(Schulz-Blaschke equation):

J₀ = η_(sp)/c  (1 + 0, 31^(×)η_(sp))  cm³/g wherein${\eta_{sp} = {\frac{t}{t_{o}} - {1\mspace{14mu} \left( {{specific}\mspace{14mu} {viscosity}} \right)}}},$

wherein t indicates the flow time of the solution with aHagenbach-Couette correction, t₀ and c indicates the concentration ofthe solution in g/cm3. Die average relative molar mass M _(v) (viscosityagent) is calculated from the following formula:

$\sqrt[0.65]{\frac{J_{o} \times 10^{2}}{3.06}}$

Polyisobutylenes according to the present invention are preferablysynthesized via a cationic polymerisation of isobutene (2-methylpropene)at a temperature ranging from about −100° C. to about 0° C. Thetemperature influences the molar mass of polyisobutylenes produced inthis way, so that the lower the temperature the higher is the molar massof the same. Usually, boron trifluoride or aluminiumtrichloride are usedin an aqueous or alcoholic solution as initiators.

Said at least one first polyisobutylene preferably has aStaudinger-Index J₀ ranging from about 22 cm3/g to about 65 cm3/g, andeven further preferred a Staudinger-Index J₀ ranging from about 25 cm3/gto about 45 cm3/g. Preferred, said at least one first polyisobutylenehas an average relative molar mass M _(V) (viscosity agent) ranging fromabout 24,000 g/mole, preferred from about 35,000 g/mole to about 130,000g/mole, preferred to about 95,000 g/mole and further preferred anaverage relative molar mass M _(V) ranging from about 30,000 g/mole,preferred from about 37,000 g/mole to about 75,000 g/mole, preferred toabout 70,000 g/mole. The at least one first polyisobutylene ispreferably comprised in a quantity of in a quantity ranging from about28% by weight to about 60% by weight, further preferred in a quantityranging from about 33% by weight to about 50% by weight, each based onthe total quantity of the composition.

Said at least one second polyisobutylene preferably has aStaudinger-Index J₀ ranging from about 400 cm³/g to about 800 cm³/g andeven further preferred a Staudinger-Index J₀ ranging from about 500cm³/g to about 700 cm³/g. Preferred, the at least one secondpolyisobutylene has an average relative molar mass M _(V) ranging fromabout 1,500,000 g/mole, preferred from about 2,000,000 g/mole, to about6,000,000 g/mole, preferred to about 5,000,000 g/mole, further preferredranging from about 3,000,000 g/mole to about 5,000,000 g/mole, preferredto about 4,800,000 g/mole.

The term butyl rubber in the sense of the present invention isespecially referred to as co- or block co-polymers of isobutene withabout 0.5% by weight to about 5% by weight of isoprene, based on thetotal quantity of said butyl rubber, which are in particular produced bycationic polymerization. Via the used isoprene and the carbon-carbondouble bonds contained in it and acting as functional groups, across-linking reaction can be initiated. In the sense of the presentinvention, the term butyl rubber comprises in particular alsohalogenized butyl rubbers, especially such being chlorinatedrespectively brominated (chlorobutyl rubber respectively bromobutylrubber). Mixtures of various butyl rubbers can also be used, which meansmore than at least one butyl rubber.

Said at least one first depolymerized butyl rubber is received bydepolymerization of butyl rubbers (IIR). Said at least one first butylrubber has a low molecular weight. It is especially preferred at 23° C.in liquid form. Comparatively, said at least one second butyl rubber isnot depolymerized and has other than said first butyl rubber a highmolecular weight. Said at least one second butyl rubber isadvantageously at 23° C. provided in a solid form.

Said at least one first depolymerized butyl rubber has an apparentBrookfield viscosity according to DIN EN ISO 2555:2000-01 at 66° C.ranging from about 600,000 mPa·s to about 1,600,000 mPa·s, furtherpreferred ranging from about 700,000 mPA·s to about 1,500,000 mPA·s.Preferably, said at least one first depolymerized butyl rubber has anaverage molecular weight M_(w) ranging from about 20,000 to about60,000. Said at least one first depolymerized butyl rubber preferablyhas already at low temperatures, in particular at room temperatures offor example 20° C. or 23° C., or even at slightly higher temperaturesfor example of 40° C. to 50° C., the property of undergoing across-linking reaction due to the unsaturated carboncarbon double bondscontained in it.

Said at least one second partly cross-linked (in the following alsoreferred to as partly pre-crosslinked) butyl rubber, having thus a lowerproportion of unsaturated bonds than usual butyl rubbers, preferably hasa Mooney viscosity ML (1+3) at 127° C. ranging from about 70 MU to about93 MU, further preferred ranging from about 78 MU to about 91 MU,measured according to ISO 289:2005 or according to ASTM 1604-04. Thespecific density of said at least one second partly cross-linked butylrubber is preferably at a temperature of 25° C. according to ASTM D1875in the version of 2003 ranging from 0.5 to 1.1, preferred ranging fromabout 0.9 to about 0.98.

Preferred, said first compound is comprised by the composition accordingto the invention in a quantity ranging from about 20% by weight to about66% by weight, preferred in a quantity ranging from about 28% by weightto about 60% by weight, further preferred in a quantity ranging fromabout 33% by weight to about 50% by weight, each based on the totalquantity of the composition. Especially preferred, said first compoundis selected from a group exclusively comprising at least one firstpolyisobutylene, preferred one first polyisobutylene. In an alternativeembodiment, said first compound is selected from a group exclusivelycomprising at least one first depolymerized butyl rubber, preferredexactly one first depolymerized butyl rubber. In a further alternativeembodiment of the present invention, said first compound is a mixture ofat least one first polyisobutylene and at least one first depolymerizedbutyl rubber, preferred a mixture of exactly one first polyisobutyleneand exactly one first depolymerized butyl rubber. As far as a mixture ofat least one first polyisobutylene and at least one first depolymerizedbutyl rubber is provided, preferred said at least one firstpolyisobutylene and said at least one first depolymerized butyl rubberare contained in an approximately same quantity in said composition.However, it may also be provided that a larger quantity of said at leastone first polyisobutylene compared to said at least one firstdepolymerized butyl rubber is contained in it and vice versa.

Especially preferred, the second compound is comprised by saidcomposition in a quantity ranging from about 1% by weight to about 20%by weight, further preferred in a quantity ranging from about 2% byweight to about 10% by weight, even further preferred in a quantityranging from about 3% by weight to about 8% by weight, each based on thetotal quantity of said composition. Said second compound is in a firstembodiment preferably selected from a group exclusively comprising atleast one second polyisobutylene, preferred exactly one secondpolyisobutylene. In an alternative embodiment, the compound is selectedfrom a group exclusively comprising at least one second partlycross-linked butyl rubber, preferred exactly one second partlycross-linked butyl rubber. In a further alternative embodiment, saidsecond compound is selected from a mixture of at least one secondpolyisobutylene and at least one second partly cross-linked butylrubber, preferred, a mixture of exactly one second polyisobutylene andone second partly cross-linked butyl rubber. As far as a mixture of atleast one second polyisobutylene and at least one second, partlycross-linked butyl rubber is provided, in a preferred embodiment said atleast one second polyisobutylene and said at least one second partlycross-linked butyl rubber can be comprised in said composition inapproximately the same quantity. In a further embodiment however,varying quantities of said at least one second polyisobutylene and saidat least one second partly cross-linked butyl rubber may also becomprised.

The ratio between said at least one first compound and said at least onesecond compound in the composition according to the invention ispreferably ranging from about 15:1 to about 1:1, further preferredranging from about 13:1 to about 5:1.

The higher the amount of said at least one second compound is in thecomposition according to the invention, the higher is in general thepeel strength/the peel resistance. This is however accompanied by thedisadvantage, that in a peel test, in case of high quantities of said atleast one second compound, a rather adhesive and thus sustainableseparation image is obtained.

The composition according to the invention preferably provides goodvalues for the peel resistance and thus a good adhesion of the inventiveanti-corrosion composition for example to steel surfaces of pipes or thelike and at the same time a required cohesive separating image. Comparedto a cohesive separation, an adhesive separation or an adhesiveseparation image which would be received between an anti-corrosioncomposition and the material covering it, as for example on a steelpipe, would be disadvantageous. In case of a cohesive separation or acohesive separation image, when detaching the anti-corrosion compositionfrom the protected product, it remains on the covered product at leastin parts, as for example on a steel pipe. A mixture of at least onefirst and at least one second polyisobutylene moreover preferablyprovides an anti-corrosion composition which is not only sufficientlypourable to be used as a spattling compound, but also for example as atape or pad, for example in wrapping tapes.

The anti-corrosion composition according to the invention does apartfrom said at least one first and said at least one second compound,preferably not provide any plasticizer, in particular no plasticizer inthe form of a process oil. The use of such plasticizer can be spared assaid at least one first compound is provided in a rather liquid and nottoo viscous form due to its relatively low molecular weight, which makesthe use of plasticizers unnecessary. However, according to theinvention, the use of a plasticizer, especially in the form of a processoil can be provided. As far as provided, the anti-corrosion compositionaccording to the invention can comprise at least one process oil as aplasticizer, preferred in a quantity ranging from about 0.5% by weightto about 10% by weight, further preferred in a quantity ranging fromabout 2% by weight to about 8% by weight, each based on the totalquantity of the composition according to the invention.

The anti-corrosion composition bears the advantage that it shows goodvalues for the peel strength/peel resistance according to DIN 10268 inthe version 1999-03 already at room temperatures of for example 23° C.,in particular values being higher than about 5 N/cm, even furtherpreferred higher than about 10 N/cm, while preferred are the values forthe peel strength/peel resistance according to DIN EN 10268 in theversion 1999-03 ranging from about 6 N/cm to about 20 N/cm, even furtherpreferred from about 10 N/cm to about 40 N/cm. The aforementioned valuesare based on the mechanical peel testing according to the DIN EN 10268in the version 1999-03, and are exactly based on either applying theanti-corrosion composition onto a factory coating of for example a pipelide a gas pipeline or pipeline, as well as based on an outer pipesurface which is not coated as for example a steel pipe.

Due to its good values for the peel strength respectively the peelresistance, the anti-corrosion composition according to the inventionhas a high mechanical strength. This also applies in case of highertemperatures. The anti-corrosion composition according to the inventionpreferably also has a good adhesion to substrates of each kind, inparticular to pipes such as pipe-lines or systems comprising pipes,equally whether they have already been provided with a factory coatingor not, which means in the last case having a metal surface, inparticular a steel surface for applying said anti-corrosion composition.Especially advantageous is that it is possible to apply theanti-corrosion composition without previously applying a primer/adhesiveagent, which means that the work and time consuming pretreatment withthese products can be omitted. However, according to the invention, theuse of a primer or adhesive agent is not to be excluded. Suitableproducts are for example made of butyl rubber in mixtures withhydrocarbon resins and petrol as a solvent, which can for example beobtained under the name DENS OLEN Primer, at DENSO GmbH, Leverkusen,Germany.

Preferred, the anti-corrosion composition according to the inventioncomprises at least a third compound, selected from a group comprising atleast a third polyisobutylene with a Staudinger index J₀ ranging fromabout 75 cm³/g to about 235 cm³/g and with an average relative molarmass M _(V) ranging from about 150,000 g/mole, preferred from about160,000 g/mole, to about 950,000 g/mole, preferred to about 850,000g/mole and/or at least a third butyl rubber with an average molecularweight M_(w) ranging from about 150,000 to about 2,000,000 and a Mooneyviscosity ML(1+8) at 125° C. ranging from about 20 MU to about 62 MU,measured according to ISO 289:2005.

Said at least one third polyisobutylene preferably has a Staudingerindex J₀ ranging from about 106 cm³/g to about 160 cm³/g. Preferred,said at least one second polyisobutylene has an average relative molarmass M _(V) ranging from about 250,000 g/mole to about 600,000 g/mole,preferred to about 550,000 g/mole. Preferred, said at least one secondpolyisobutylene is comprised in a quantity ranging from about 10% byweight to about 35% by weight, further preferred in a quantity rangingfrom about 13% by weight to about 28% by weight, each based on the totalquantity of the composition.

The ratio between said at least one first polyisobutylene, i.e. thetotal quantity of said used first polyisobutylene, even if it is amixture, and said at least one second polyisobutylene, i.e. the totalquantity of said second polyisobutylene, even if it is a mixture, ispreferably ranging from about 2.5:1 to about 1:2.5, further preferredranging from about 2.2:1 to about 1:1.

The polyisobutylenes used according to the invention, i.e. the first,the second as well as the third polyisobutylene, preferably have a glasstransition temperature Tg, (measured calorimetrically by DSC) of below−50° C., further preferred below −58° C. Especially preferred, the glasstransition temperature of said at least one first, of said at least onesecond and of said at least one third polyisobutylene is ranging fromabout −55° C. to about −68° C., further preferred ranging from about−58° C. to about −68° C., further preferred ranging from about −58° C.to about −66° C. Said higher molecular, at least one secondpolyisobutylene can thus still be regarded as a highly viscous liquidand shows a certain creep tendency.

Said at least one third butyl rubber preferably has an average molecularweight M_(w) ranging from about 200,000 to about 1,800,000, furtherpreferred ranging from about 250,000 to about 600,000. Preferred, saidat least one third butyl rubber has a Mooney viscosity ML(1+8) at 125°C. ranging from about 30 MU to about 60 MU, further preferred rangingfrom about 40 MU to about 59 MU, even further preferred ranging fromabout 40 MU to about 55 MU, measured according to ISO 289:2005. Said atleast one third butyl rubber is preferably comprised by the compositionin a quantity ranging from about 10% per weight to about 50% per weight,further preferred in a quantity ranging from about 15% by weight toabout 35% by weight, each based on the total quantity of thecomposition.

Preferably, said at least one third butyl rubber comprises volumes ofunsaturation ranging from about 1 mole-% to about 3 mole-%, furtherpreferred ranging from about 1.3 mole-% to about 2.5 mole-%. This meansthat preferred, 1 mole-% to about 3 mole-%, further preferred about 1.3mole-% to about 2.5 mole-% of unsaturated compounds, i.e. carbon-carbondouble bonds as functional groups in the at least third butyl rubber arecomprised. Especially preferred, said at least one third butyl rubber isproduced by co-polymerization of isobutene and isoprene in methylchloride as a solvent. The unsaturation (the degree of unsaturation) ofthe at least one third butyl rubber can also be at about 1.5 mole-%,especially at 1.5±0.5 mole-%.

In an especially preferred embodiment, said at least one third compoundis comprised by the composition in a quantity ranging from about 10% byweight to about 40% by weight, preferred ranging from about 15% byweight to about 35% by weight, further preferred in a quantity rangingfrom about 16% by weight to about 30% by weight, each based on the totalquantity of the composition. Said at least one third compound can beselected in an embodiment exclusively from a group comprising at leastone third polyisobutylene, preferred exactly one third polyisobutylene.In an alternative embodiment, said at least one third compound can beselected from a group comprising at least one third butyl rubber,preferred exactly one third butyl rubber. In a further alternativeembodiment it may also be provided that said at least one third compoundis selected from a group comprising at least one third polyisobutyleneand at least one third butyl rubber. As far as a mixture of one at leastone third polyisobutylene and at least one third butyl rubber isprovided, said at least one third polyisobutylene and said at least onethird butyl rubber can be comprised by the composition in about the samequantity. It may however also be provided that varying quantities ofsaid at least one third polyisobutylene and said at least one thirdbutyl rubber are comprised in it.

Especially preferred, the anti-corrosion composition comprises exactlyone first compound, exactly one second compound and exactly one thirdcompound. Especially preferred, the composition according to theinvention comprises as a first compound exactly one firstpolyisobutylene or exactly one first depolymerized butyl rubber, as asecond compound exactly one second polyisobutylene or exactly one secondpartly cross-linked butyl rubber, and as a third compound exactly onethird polyisobutylene or exactly one third butyl rubber. Especiallypreferred, the composition according to the invention comprises at leastone first depolymerized butyl rubber, at least one secondpolyisobutylene and as a third compound either at least one third butylrubber or at least one third polyisobutylene. Preferred, theanti-corrosion composition comprises exactly one first depolymerizedbutyl rubber, exactly one second polyisobutylene, and exactly either onethird butyl rubber or a third polyisobutylene. Preferred, in case of thementioned compositions, those butyl rubbers and polyisobutylenes areused, which further above were characterized as preferred or furtherpreferred regarding their properties and quantities.

In an alternative embodiment, the anti-corrosion composition accordingto the invention comprises as a first compound at least one firstpolyisobutylene, at least one second partly cross-linked butyl rubber asa second compound, and as a third compound either at least one thirdbutyl rubber or at least one third polyisobutylene. Preferred, thecomposition according to the invention comprises as a first compoundexactly one first polyisobutylene, as a second compound exactly onesecond partly cross-linked butyl rubber, and as a third compound eitherexactly one third butyl rubber or a third polyisobutylene. Thepolyisobutylenes and butyl rubbers comprised in the aforementionedcompounds are used with their preferred respectively further preferredproperties and quantities, as characterized further above.

Preferred, the composition according to the invention comprises at leastone first polyisobutylene in a quantity ranging from about 30% by weightto about 50% by weight, at least one second partly cross-linked butylrubber in a quantity ranging from about 2% by weight to about 10% byweight, and a third polyisobutylene in a quantity ranging from about 12%by weight to about 30% by weight or a third butyl rubber in a quantityranging from about 12% by weight to about 30% by weight, wherein thepercent-by-weight quantities are each based on the total quantity of thecomposition according to the invention. In an alternative embodiment,the composition according to the invention comprises about 30% by weightto about 50% by weight of one first depolymerized butyl rubber, about 2%by weight to about 10% by weight of a second polyisobutylene, and about12% by weight to about 30% by weight of at least one thirdpolyisobutylene or about 12% by weight to about 30% by weight of atleast one third butyl rubber, wherein the percent-by-weight quantitiesare each based on the total quantity of the composition according to theinvention. In case of the aforementioned compositions, thepolyisobutylenes and butyl rubbers used have the preferred or furtherpreferred properties as characterized further above.

In a preferred embodiment, optionally in combination with one first,second and/or third butyl rubber as above defined, independently of eachother

-   the at least one first polyisobutylene has a Staudinger index J₀    ranging from about 15 cm³/g to about 70 cm³/g and an average    relative molar mass M _(V) (viscosity agent) ranging from about    14,000 g/mole to about 147,000 g/mole;-   the at least one second polyisobutylene has a Staudinger index J₀    ranging from about 240 cm³/g to about 900 cm³/g and an average    relative molar mass M _(V) (viscosity agent) ranging from about    980,000 g/mole to about 7,493,000 g/mole; and-   the at least one third polyisobutylene has a Staudinger index J₀    ranging from about 75 cm³/g to about 235 cm³/g and an average    relative molar mass M _(V) (viscosity agent) ranging from about    164,000 g/mole to about 950,000 g/mole.

In a preferred embodiment, optionally in combination with one first,second and/or third butyl rubber as above defined, independently of eachother

-   the at least one first polyisobutylene has a Staudinger index J₀    ranging from about 24.9 cm³/g to about 54.4 cm³/g and an average    relative molar mass M _(V) (viscosity agent) ranging from about    30,000 g/mole to about 100,000 g/mole;-   the at least one second polyisobutylene has a Staudinger index J₀    ranging from about 227.0 cm³/g to about 820.6 cm³/g and an average    relative molar mass My (viscosity agent) ranging from about 900,000    g/mole to about 6,500,000 g/mole; and-   the at least one third polyisobutylene has a Staudinger index J₀    ranging from about 70.8 cm³/g to about 218.7 cm³/g and an average    relative molar mass M _(V) (viscosity agent) ranging from about    150,000 g/mole to about 850,000 g/mole.

In a further preferred embodiment, the anti-corrosion compositioncomprises

-   at least one first compound selected from a group comprising at    least one first polyisobutylene with an average relative molar mass    M ^(V) ranging from about 35,000 g/mole to about 90,000 g/mole    and/or at least one first depolymerized butyl rubber with an    apparent viscosity according to Brookfield at 66° C. according to    DIN EN ISO 2555:2000-01 ranging from about 500,000 mPa·s to about    2,000,000 mPa·s, an average molecular weight M_(w) ranging from    about 30,000 to about 45,000 and a degree of unsaturation of 2.0 to    4.0 mole-%;-   at least one second compound selected from a group comprising at    least one second polyisobutylene with an average relative molar mass    M _(V) ranging from about 1,000,000 g/mole to about 4,000,000 g/mole    and/or at least one second, partly crosslinked butyl rubber with a    Mooney viscosity ML(1+3) at 127° C. ranging from about 60 MU to    about 90 MU according to ISO 289:2005 and a degree of unsaturation    of below 1.0 mole-%; and-   optionally at least one third compound selected from a group    comprising at least one third polyisobutylene with an average    relative molar mass M _(V) ranging from about 200,000 g/mole to    about 800,000 g/mole and/or at least one third butyl rubber with an    average molecular weight M_(w) ranging from about 150,000 to about    2,000,000, a Mooney viscosity ML(1+8) at 125° C. ranging from about    40 MU to about 60 MU, measured according to ISO 289:2005, and a    degree of unsaturation of below 1.0 to 2.0 mole-%,    wherein the anti-corrosion composition comprises at least one first    or at least one second polyisobutylene as well as at least one first    or at least one second butyl rubber.

In a further preferred embodiment, the anti-corrosion compositionaccording to the invention comprises one first, second and thirdpolyisobutylene, each having the above-mentioned values, preferably thementioned preferred values, for the Staudinger index J₀ and the averagerelative molar mass (viscosity agent), in particular exactly one first,exactly one second and exactly one third polyisobutylene, each of whichhaving the above-mentioned values, preferably the mentioned preferredvalues, for the Staudinger index J₀ and the average relative molar massM _(V) (viscosity agent).

Preferably, the composition according to the invention comprises besidessaid mentioned at least one first, at least one second and/or at leastone third compounds, a filler material, at least one antioxidant, atleast one cross-linking agent, at least an elastomer and/or at least onestabilizer. The above-mentioned further components can be added to thecomposition according to the invention separately or in mixtures.Especially preferred, the anti-corrosion composition according to theinvention comprises besides said at least one first and at least onesecond compound, further preferred also besides the at least one thirdcompound, at least one filler material. Said at least one fillermaterial is preferably comprised by the composition in a quantityranging from about 20% by weight to about 70% by weight, furtherpreferred in a quantity ranging from about 30% by weight to about 65% byweight, and even further preferred in a quantity ranging from about 33%by weight to about 50% by weight, each based on the total quantity ofit. Especially preferred, said at least one filler material is powderyor fibrous. The term fibrous in the sense of the present invention alsoincludes such filler materials having a needle-shaped structure.Especially preferred, the composition according to the inventioncomprises at least one first powdery filler material and at least onesecond fibrous filler material. Especially preferred in case of addingsuch a mixture of at least one powdery and at least one fibrous fillermaterial, said fibrous filler material is added at a quantity up to amaximum of the quantity of the powdery filler material. A powdery aswell as a fibrous filler material can each be comprised by saidcomposition in a quantity ranging from about 10% by weight to about 40%by weight, preferred in a quantity ranging from about 12% by weight toabout 25% by weight, each based on the total quantity of saidcomposition.

Preferred, said at least one filler material is selected from a group ofthe powdery mineral filler materials or of the mineral and/or organicfibrous filler materials. It may for example be of metal, zinc oxide,cellulose fibers, of needle-shaped wollastonite or the like. It may alsobe selected from a group of organic fibers as for example fromacrylonitrile fibers with a length ranging from about 1.5 mm to about 20mm, further preferred with a length of about 4 mm to about 15 mm, and afineness ranging from about 0.5 dtex to about 100 dtex, furtherpreferred with a fineness ranging from about 1 dtex to about 20 dtex,each measured according to ISO 1144 in the version of 1973. As far as apowdery filler material, in particular a mineral powdery filler materialis used, it preferably has a residue in % at a sieve analysis accordingto DIN 66165 in the version 1987-04 at H-100 (100 μm) from about 1% toabout 5%, at H-60 (60 μm) from about 1% to about 5% and at H-30 (30 μm)ranging from about 1% to about 5%. Preferably, the anti-corrosioncomposition comprises at least one filler material. If the fillermaterial is powdery, it is preferably selected from the group of mineralfiller materials and preferably is a talcum.

As far as at least one antioxidant is provided, this can be comprised bythe anti-corrosion composition according to the invention preferably ina mixture of various antioxidants in a quantity ranging from about 0.1%by weight to about 1% by weight, further preferred in a quantity rangingfrom about 0.15 to about 0.5% by weight, each based on the totalquantity of it. As far as at least one stabilizer, which may also bereferred to as a dispersing agent, is contained in the anti-corrosioncomposition according to the invention, this is preferably selected froma group comprising C₁₀₋ to C₂₄₋ carbonic acid, and is preferably astearic acid. Said at least one stabilizer is comprised by theanti-corrosion composition according to the invention preferred in aquantity ranging from about 0.05% by weight to about 0.5% by weight,based on the total quantity of said composition. As stabilizers, forexample metal salts of the mentioned carbonic acids, for example zincstearates or free carboxylic acids, as for example free fatty acids with12 to 24 carbon atoms, in particular stearic acid or oleic acid, mayalso be used.

Furthermore, the composition according to the invention can compriseother additives, which may be usually required depending on theoperational purpose. In particular, the anti-corrosion composition canfurther comprise at least one flame retardant, at least onecross-linking agent and/or at least an elastomer. As far as a flameretardant is provided, it is comprised by the anti-corrosion compositionaccording to the invention preferably in a quantity ranging from about0.02% by weight to about 2% by weight, based on the total quantity ofsaid composition.

As far as the anti-corrosion composition according to the inventioncomprises at least one cross-linking agent, it is comprised by theanti-corrosion composition according to the invention preferably in aquantity ranging from about 0.1% by weight to about 10% by weight,further preferred in a quantity ranging from 0.2% by weight to about 8%by weight, each based on the total quantity of said composition. Thecross-linking agent is comprised in particular, if the anti-corrosioncomposition is a component of a single- or multi-layered tape,especially a wrapping tape for pipes of each kind, in particularpipelines. However, it may also be comprised, in case the anti-corrosioncomposition is provided as a coating or spattling compound. Said atleast one cross-linking agent is preferably selected from a groupcomprising at least one phenolic resin. Phenolic resins are rehardenedby cross-linking reactions to become thermosetting plastics, theso-called phenoplasts. Such cross-linking reaction can occur in theanti-corrosion composition according to the invention, especially if itcomprises at least one first depolymerized or at least one second, atleast partly cross-linked or even at least one third butyl rubber or atleast one partly unsaturated polyisobutylene, as described furtherbelow. Phenolic resins are condensation products of a phenol withaldehydes, preferably with formaldehyde. In the sense of the presentinvention, the anti-corrosion composition according to the inventioncomprises at least one phenolic resin containing hydroxymethyl groups.These hydroxymethyl groups constitute the reactive respectivelyfunctional groups which trigger a cross-linking reaction which may alsobe referred to as self-hardening reaction, with said functional groups,i.e. said carbon-carbon double bonds of said at least one firstdepolymerized, said at least one second partly cross-linked and/or saidat least one third butyl rubber, or partly unsaturated polyisobutylenes.Especially preferred in the sense of the present invention is the atleast one phenolic resin produced from at least one phenol or itsderivatives and of at least one aldehyde, selected from a groupcomprising formaldehyde, acetaldehyde, benzaldehyde and/or acrolein,wherein the formaldehyde is especially preferred. As phenol derivativesparticularly tetra-butylphenol, nonylphenol or octylphenol are used, butalso aryl derivatives, especially phenylphenol, as well as divalentphenols as for example resorcinol or bisphenol A or naphthol can beused. Especially preferred are octylphenol-formaldehyde resins. Phenolresins as a cross-linking agent are in particular such being in theclass of the so-called resoles, i.e. which are produced via abase-catalyzed reaction of the mentioned starting products.

Upon wrapping an at least two-layered tape having as outer layer atleast one layer of the anti-corrosion composition according to theinvention, in overlap areas said at least one layer of theanti-corrosion composition according to the invention gets into touchwith a further layer. This further layer, e.g. a coupling layer, can inthis case advantageously comprise catalytic converters, which acceleratethe cross-linking reaction, especially at low temperatures, for exampleat a room temperature of 23° C. Suitable catalytic converters areselected from a group comprising at least one zinc chloride, zincbromide, ferric chloride, antimony chloride, antimony bromide, tinbromide, germanium chloride, cobalt bromide, nickel chloride and/ororganic salts of tin or zinc, as for example zinc stearates or zincoleates, wherein particularly preferred, tin or zinc halides, andfurther preferred, tin chloride and zinc chloride, solely or as amixture, can be used. Said catalytic converter is comprised in thisfurther layer of a tape, which does preferably not contain theanti-corrosion composition, preferably in a quantity ranging from about0.1% by weight to about 5% by weight, further preferred in a quantityranging from about 0.15% by weight to about 4.5% by weight, and evenfurther preferred in a quantity ranging from about 0.2% by weight toabout 4% by weight, each based on the total quantity of said furtherlayer.

If a catalytic converter is provided, the material comprising it canpreferably contain at least one co-reagent, selected from a groupcomprising divinyl fumarate, divinyl adipate andtriallyl-trichlorbenzol, wherein especially preferred atriallyl-trichlorbenzol is selected. The coreagent in particular servesto make the used catalyst converter acceptable for the materialcontaining the catalyst converter. Preferably, the co-reagent iscomprised in the material containing the catalyst converter in aquantity ranging from about 0.5% by weight to about 5% by weight,further preferred in a quantity ranging from about 2% by weight to about4.5% by weight, based on the total quantity of said material containingthe catalyst converter.

Said at least one elastomer is preferably selected from a groupcomprising at least an ethylene-propylene-diene-rubber. Especially suchco- or block-co-polymers as well as terpolymers are meant here, whichhave a carbon-carbon double bond as functional groups. Hereof it is alsopossible to use mixtures. Especially preferred are terpolymers beingformed in a polymerisation reaction with ethylene, propylene and onediene. They are also called EPDM terpolymers and combine one saturatedpolymer backbone with unsaturated rests in side groups. Especiallypreferred in the sense of the present invention in this case5-ethylidene-2-norbornens, dicyclopentadien and/or5-vinylidene-2-norbornes as a diene are used in quantities up to about15% by weight, preferred in quantities ranging from about 0.3% by weightto about 12% by weight. In case of using 5 ethyliden-2-norbornes,preferably quantities ranging from about 4% by weight to about 11% byweight and in case of using dicyclopentadien, quantities ranging fromabout 1.0% by weight to about 6.0% by weight are used. Theabove-mentioned percent-by-weight quantities are based on the totalquantity of monomers being used in a polymerization to an EPDMrespectively ethylene-propylene-rubber.

An especially preferred anti-corrosion composition according to theinvention comprises about 30% by weight to about 50% by weight of saidat least first compound, about 2% by weight to about 10% by weight ofsaid at least one second compound, about 12% by weight to about 30% byweight of said at least one third compound, and about 25% by weight toabout 45% by weight of at least one filler material, wherein thequantities are each based on the total quantity of the anti-corrosioncomposition according to the invention.

In an especially preferred embodiment, the anti-corrosion compositionaccording to the invention comprises about 35% by weight to about 45% byweight of exactly one first polyisobutylene, about 3% by weight to about7% by weight of exactly one second partly cross-linked butyl rubber,about 15% by weight to about 25% by weight of exactly one thirdpolyisobutylene and about 30% by weight to about 40% by weight of twofiller materials, wherein one filler material is a mineral powderyfiller material and the other filler material is a mineral needle-shapedfiller material. In a further preferred embodiment, the anti-corrosioncomposition according to the invention comprises about 35% by weight toabout 45% by weight of exactly one first depolymerized butyl rubber,about 3% by weight to about 7% by weight of exactly one secondpolyisobutylene, about 15% by weight to about 25% by weight of exactlyone third polyisobutylene or of one third butyl rubber, and about 40% byweight to about 45% by weight of a filler material, selected from agroup of mineral powdery filler materials.

In the aforementioned preferred and especially preferred compositions ofthe anticorrosion composition according to the invention furthermore, ifrequired, about 0.1% by weight to about 0.5% by weight of at least onestabilizer and/or 0.15% by weight to about 0.6% by weight of at leastone antioxidant can be comprised by the composition according to theinvention, each based on the total quantity of it.

As far as in the present invention the term “about” is used for values,value ranges or terms containing values, those values are to be meantwhich are regarded as professionally usual in this context by a personskilled in the art. In particular comprised by the term “about” aredeviations of the mentioned values, value ranges or terms containingvalues of +−10%, preferred +−5%, further preferred +−2%.

The anti-corrosion composition may further comprise at least onetackifier, in particular a hydrocarbon resin, in a quantity ranging fromabout 5% by weight to about 25% by weight, further preferred in aquantity ranging from about 8% by weight to about 20% by weight, eachbased on the total quantity of the anti-corrosion composition accordingto the invention.

Especially preferred, the anti-corrosion composition is provided in atape or pad format. Especially preferred is the tape format.

Especially preferred, the tape is formed at least single-layered,further preferred, it is formed at least two-layered, but may also beformed three, four, five or multi-layered. It can for example be formedin a way that it has two outer layers comprising the anti-corrosioncomposition according to the invention, which encompass an inner layerformed of a carrier foil which is in particular made of at least apolyethylene and/or polypropylene, preferred of a polyethylene. Thecarrier foil which can have the effect of an anti-jackknife brake,depending on its thickness, may in this case have a coupling layer onone or both sides of it, facing the layers of the anti-corrosioncomposition according to the invention.

It may also be provided that the tape has only one single layer made ofthe anticorrosion composition according to the invention, which isbonded with a carrier foil, in particular with such as above defined,wherein the carrier foil may have a coupling layer on one or both sides.In case of this construction, the carrier foil, serving primarily tostabilize the layer made of the anti-corrosion composition according tothe invention, has a certain thickness, preferably ranging from about0.2 mm to about 1.2 mm, further preferred from about 0.3 mm to about 0.7mm. Further preferred, the carrier foil has coupling layers on both ofits outer surfaces of the same or different compositions. The carrierfoil may preferably have a coupling layer on its side facing the layerformed of the anti-corrosion composition according to the invention,which is formed of the same material as the carrier foil and of said atleast one second and/or at least one third polyisobutylene and/or the atleast one second partly cross-linked and/or an at least one third butylrubber of the layer made of the anti-corrosion composition according tothe invention, preferred exclusively of said aforementioned materials.The further coupling layer being applied to the side of the carrier foilnot facing the layer made of the anti-corrosion composition, canhowever, especially if an at least one-layered second tape is providedin particular for mechanical protection, which can be wrapped around thetape comprising the anti-corrosion composition according to theinvention on the respective product, of besides at least one secondand/or at least one third polyisobutylene and/or said at least onesecond partly cross-linked and/or an at least one third butyl rubberaccording to the inventive composition and of the material of thecarrier foil, in particular a polyethylene and/or polypropylene, and maycomprise tackifiers, especially in the form of hydrocarbon resins aswell as antioxidants and in particular the catalytic converters and/orco-reagents for those. The catalytic converter and/or co-reagent can inthis case especially at higher temperatures, in particular such fromabout 50° C., preferred such ranging from about 55° C. to about 220° C.,further preferred ranging from about 60° C. to about 140° C., initiatethe cross-linking reaction in said at least one second partlycross-linked and/or at least one third butyl rubber, and, ifappropriate, also in the further available elastomer, as abovedescribed. The catalytic converter, separately or in a mixture, iscomprised in the outer coupling layer preferably in a quantity rangingfrom about 0.1% by weight to about 10% by weight, preferred ranging fromabout 0.15% by weight to about 4% by weight, each based on the totalquantity of the outer coupling layer. Upon wrapping or applying the tapewith at least one layer made of the anticorrosion composition accordingto the invention onto tubular or other articles having an overlap, across-linking can be initiated in the overlap area, preferably at raisedtemperatures, if at least one catalytic converter is provided in theouter coupling layer, by which a stronger bonding, particularly withoutwrinkle formation can be achieved in the overlap area.

Said tape comprising the anti-corrosion composition according to theinvention can be constructed particularly in a symmetrical, but also inan asymmetrical form. A symmetrically formed tape has, as above alreadydescribed, a carrier foil comprising for example at least onepolyethylene and/or polypropylene, being on its two outer surfaces eachencompassed by one layer made of the anti-corrosion composition. The twoouter layers do preferably have approximately the same thickness. Inthis case, between the carrier foil and the layers comprising theanti-corrosion composition at least one coupling layer may be provided,as above also described. If the coupling layer is applied on both sidesof the carrier foil, it also has approximately the same strength. Inthis case this is referred to as a symmetrically constructed 3-respectively 5-layered respectively 5-sheet-tape, the coupling layers inthe last-mentioned case included.

An asymmetrically constructed tape may also be provided. This can forexample be constructed in a way that one layer being made of theanti-corrosion composition according to the invention and facing theproduct to be covered, is bonded with a carrier foil as above defined.In this case, at least one coupling layer can be applied between thelayer comprising the anticorrosion composition according to theinvention and said carrier foil. On the side of said carrier foil notfacing the layer made of the anti-corrosion composition according to theinvention, for example another layer made of the anti-corrosioncomposition according to the invention may be provided, which has alower thickness than the layer facing the article to be wrapped. Saidcarrier foil on the side not facing said layer made of theanti-corrosion composition according to the invention can also have afurther coupling layer, which preferably also comprises at least onefirst and/or at least one third polyisobutylene and/or at least onesecond, partly cross-linked and/or at least one third butyl rubber aswell as the material of the carrier foil, and further preferred inaddition tackifiers like hydrocarbon resins, catalytic converters,co-reagents and other additives, as above already described.

In the sense of the present invention it may also be provided that saidtape having a layer made of the anti-corrosion composition according tothe invention comprises at least one layer of an anti-jackknife brake.In this case, said tape may for example be formed in a way that itcomprises one single layer made of the anti-corrosion compositionaccording to the invention, wherein approximately in the center, a verythin intermediate layer, preferred of a strength ranging from about 15μm to about 100 μm, further preferred ranging from about 20 μm to about75 μm, is applied. Said intermediate layer serves as an anti-jackknifebrake and prevents the tape from overstretching, particularly in case ofa spiral wrapping of the same around an article to be wrapped as forexample a pipeline. Especially preferred, said anti-jackknife brakerespectively said intermediate layer is formed of at least onepolyethylene and/or polypropylene and is especially preferred apolyethylene foil, in particular made of an LDPE or LLDPE. A layer madeof the anti-corrosion composition provided with such an anti-jackknifebrake can also be referred to as two- or alternatively as three-layered.In this case, said anti-jackknife brake may be arranged in the tapesymmetrically approximately in the center, but also asymmetricallyshifted to the top or bottom side of it. However, preferred is asymmetrical arrangement approximately in the center, i.e. at half of thestrength of the tape, as far as it comprises only one more layer made ofthe anti-corrosion composition according to the invention. As alreadydescribed above, it may however also be provided that on top of saidanti-jackknife brake on the side of the tape not facing the product tobe wrapped, a further layer is applied which comprises for example acatalytic converter, for example an adhesive layer. In this case, a realthree-layered tape is provided.

The aforementioned coupling layers preferably comprise the at least onesecond and/or at least one third polyisobutylene and/or the at least onesecond partly cross-linked and/or at least one third butyl rubber of theanti-corrosion composition according to the invention and at least onepolyethylene and/or polyprobylene. Especially preferred, these comprise,preferred besides at least one second partly cross-linked and/or atleast one third buty rubber, at least one second or at least one thirdpolyisobutylene, preferred at least one third polyisobutylene, evenfurther preferred exactly one third polyisobutylene or a mixture of asecond and third polyisobutylene, wherein the quantities of the used atleast one second and/or third polyisobutylene is in a range from about35% by weight to about 65% by weight, further preferred in a range fromabout 40% by weight to about 60% by weight, each based on the totalquantity of the coupling layer. In an alternative embodiment, theaforementioned coupling layers comprise at least one second partlycross-linked and/or at least one third butyl rubber, preferred at leastone second or at least one third butyl rubber, even further preferredexactly one second or one third butyl rubber or a mixture of a secondand a third butyl rubber, wherein the quantity of the used at least onesecond and/or third butyl rubber is in a range from about 35% by weightto about 65% by weight, further preferred in a range from about 40% byweight to about 62% by weight, each based on the total quantity of thecoupling layer. Said at least one polyethylene and/or polypropylene,preferably at least one polyethylene, in particular one LPDE or LLDPE,further preferred exactly one polyethylene, is comprised by the couplinglayer in a quantity ranging from about 25% by weight to about 65% byweight, further preferred ranging from about 30% by weight to about 60%by weight, each based on the total quantity of the coupling layer. Acomposition of a coupling layer exclusively comprises the at least onesecond and/or at least one third butyl rubber and the at least onepolyethylene and/or polypropylene, preferred exactly one second or onethird butyl rubber and exactly one polyethylene, but no furtheradditives.

A further composition of a coupling layer comprises besides said atleast one second and/or at least one third polyisobutylene and or the atleast one second and/or at least one third butyl rubber and the at leastone polyethylene and/or polypropylene further additives, namelypreferably tackifiers, antioxidants, catalytic converters, co-reagents,as in particular above described, as well as color pigments. In thiscase, for example a tackifier in a quantity ranging from about 5% byweight to about 15% by weight, further preferred in a quantity rangingfrom about 7% by weight to about 13% by weight can be provided beingpreferably selected from a group comprising hydrocarbon resins.Moreover, at least one antioxidant may be provided, preferably in aquantity ranging from about 0.05% by weight to about 0.5% by weight,further preferred in a quantity ranging from about 0.1% by weight toabout 0.5% by weight. Said antioxidant can in this case particularly beselected from a group comprising sterically hindered phenols, as forexample pentaerythritol-tetrakis(3-(3.5-di-ter-butyl-4-hydroxyphenyl)propionate). Furthermore, saidcoupling layer can also comprise at least one pigment, in particularsuch having the form of a masterbatch. Said at least one pigment isprovided in a composition of the coupling layer in a quantity rangingfrom about 0.5% by weight to about 3% by weight, further preferred in aquantity ranging from about 0.9% by weight to about 2% by weight. Theaforementioned quantities given in percent by weight for said tackifier,said antioxidant and said pigment each refer to the total quantity ofthe coupling layer. Said pigment can for example be a black pigment, inorder to convey a uniform appearance of the tape. However, each otherpigment as for example a red one can also be used to highlight and tomark the presence of a coupling layer. the coupling layer has preferablya strength ranging from about 10 μm to about 150 μm, further preferred astrength ranging from about 20 μm to about 100 μm, even furtherpreferred a strength ranging from about 25 μm to about 80 μm.

Said carrier foil, as far as it is not formed as a anti-jackknife brake,preferably has a thickness ranging from about 0.2 mm to about 1.2 mm,further preferred a thickness ranging from about 0.3 mm to about 0.8 mm.Said carrier foil is preferably made of polyethylene or polypropylene,and is preferred made of a polyethylene. Especially preferred, saidcarrier foil is formed from a group comprising polyethylenes, which canbe electron-beam crosslinked. If said carrier foil is used with couplinglayers, said coupling layers also contain a polyethylene which can beelectron-beam crosslinked, preferably the same polyethylene beingcontained in said carrier foil. Further preferably, said carrier foilhas been slightly stretched, so that it advantageously has a tendency toshrink when being heated and thus, a possible length expansion uponheating can be overcompensated. Further, upon application by wrappingtubular articles, the contact pressure in direction of the tubulararticle is also increased.

If said carrier foil has a coupling layer on one or on both sides, thecomplete composite will preferably be slightly stretched. A compositefoil produced in this way will followingly be coated with theanti-corrosion composition according to the invention on at least oneside. This layer preferably has a thickness ranging from about 0.25 mmto about 2.0 mm, further preferred a thickness ranging from about 0.35mm to about 1.3 mm. If said carrier foil is coated with a coupling layeron both sides and if said carrier foil is coated with the anti-corrosioncomposition only on one side, the outer coupling layer preferablycomprises catalytic converters, if appropriate also co-reagents forthem, as above described. The composition of the adhesion layers appliedon both sides of said carrier foil can thus be different, especiallypreferred in the sense of the present invention. The above describedtape construction has the advantage that on the one hand a cross-linkingreaction is also initiated in the overlap area upon wrapping or applyingsuch a tape via the provided catalytic converter, as far as inparticular the at least one second and/or the at least one third butylrubber is contained, and, no matter whether applied with overlap or not,said tape can be wrapped for example with an identical further tape,wherein said at least one catalytic converter contained in said outercoupling layer initiates the cross-linking of the part of the furthertape comprising the anti-corrosion composition according to theinvention facing said tape. Said carrier foil can comprise furtheradditives as for example pigments, antioxidants orstabilizers/disperging agents. In a further embodiment of the presentinvention, the anticorrosion composition according to the invention canalso be applied on one side of a shrink sleeve or a shrink tape. Inaddition to providing a good adhesion by cross-linking as a result ofthe specific composition of the anti-corrosion composition according tothe invention, due to the heating of the shrink sleeve respectively theshrink tape required for the shrinking, a further thermal activation ofthe anti-corrosion composition according to the invention can beprovided, so that the cross-linking reaction is supported which causesan even stronger bonding of such system in particular to a tubulararticle.

In addition to said aforementioned at least single-layered tapecomprising the anticorrosion composition according to the invention, asecond tape may be provided for giving mechanical protection. Saidsecond tape is constructed at least single-layered, and is preferablyconstructed in a single-, two- or three-layered form. However, it mayalso be constructed in a four- or even multiple-layered form. The secondtape is meant to be a mechanical protection tape. Said second tapecomprises preferably a layer made of at least one polyethylene and/orpolypropylene, preferred at least one polyethylene, preferred anelectron-beam-crosslinked polyethylene of sufficient strength. As far aspolyethylene is used, it preferably comprises an ultimate elongationaccording to EN ISO 527 in the version of 2012-06 of >300%, furtherpreferred >400%, even further preferred >500%, preferred such rangingfrom about 300% to about 800%. Further preferred, it has a tensilestrength according to EN ISO 527 in the version of 2012-06 ranging fromabout 8 MPa to about 25 MPa, further preferred ranging from about 12 toabout 20 MPa. The second tape can for example also be used to wrap twoidentical tapes comprising the anticorrosion composition according tothe invention around a tubular article. The identity of theaforementioned tapes with the anti-corrosion composition advantageouslyconsists in an identical construction and/or identical chemicalcomposition.

Said at least one layer made of polyethylene and/or polypropylene,preferably exactly one layer, of the second tape can be provided with anadhesive layer on one side. However, it may also be provided that it isformed on one side with an adhesive layer of at least one first and/orat least one third butyl rubber or at least one first polyisobutyleneand/or at least one third polyisobutylene according to theanti-corrosion composition of the invention. However, this layer cancomprise even further additives. As far as one adhesive layer is bondedwith said layer of at least one polyethylene and/or polypropylene, asdescribed above, for the second tape it is in this case preferablyprovided that between these two layers a layer for achieving asufficient coupling is provided, wherein this can have a composition asdescribed further above in connection with a tape comprising theanti-corrosion composition according to the invention.

Moreover, a pipe protection pad can furthermore be provided which iswrapped around said at least one tape with at least one layer made ofthe anti-corrosion composition according to the invention, ifappropriate even in combination with a second tape, which serves as acover and protection tape, providing an advantageous, in particularload-distributing effect on the wrapping with said at least one tapearranged underneath the pipe protection pad.

Each product subject to possible corrosion can be protected with theanti-corrosion composition according to the invention, in particular bycovering if applied as a tape or pad (foil) or if applied by grouting orspackling the mass in order to form a coating. Especially preferred, theanti-corrosion composition is used for pipes and systems comprisingpipes. In particular, the anti-corrosion composition is used forwrapping pipelines of each kind, but also for wrapping gas pipelinesetc. It can also be used for other technical plants and/or in areasbeing subject to possible corrosion, and this not only as a wrapping,but also for example as a support/cover, the aforementioned in case ofproviding it as an at least single-layered tape or at leastsingle-layered pad, but also as a coating made of a mixture of theanti-corrosion composition according to the invention, which can begrouted or spackled.

The present invention further relates to the use of the anti-corrosioncomposition according to the invention as described further above forprotecting pipes and systems comprising pipes as well as other plantsand installations from corrosion. Furthermore, the present inventionalso relates to a method for achieving anti-corrosion on pipes andsystems comprising pipes as well as other plants and installations byapplying the anti-corrosion composition according to the invention.Especially preferably according to the invention, an at leastsingle-layered tape comprising the anti-corrosion composition accordingto the invention is wrapped around pipes respectively systems comprisingpipes. And finally, the present invention relates to at least onesingle-layered wrapping tape comprising the anti-corrosion compositionaccording to the invention, as above described.

The present invention is explained in more detail based on the followingexamples. Here, it should be mentioned in advance that the featuresindicated in the examples may be combined with each single or with eachother of all features described in the general description. Inparticular, the composition of the anti-corrosion composition accordingto the invention in tape format is just an example.

In total, six comparative compositions 1 to 6 and four anti-corrosioncompositions according to the invention 7 to 10 were prepared, whereintheir composition can be taken from the following table, which alsoindicates the peel strengths/peel resistances, defined according to DINEN 12068 in the version 1999-03. All numerical values in the followingtable are—unless indicated otherwise—indicated in weight percent (% byweight), each value being based on the total quantity of each of thecompositions 1 to 10.

Composition No. 1 2 3 4 5 6 7 8 9 10 First polyisobutylene 30 39.1 32.533 30 40 40 40 First depolymerized 39.5 37 butyl rubber Thirdpolyisobutylene 20 20 21 20 15 Second polyisobutylene 5 3 8.5 Secondpartly pre-crosslinked 5 10 butyl rubber Third butyl rubber 10 17.4 9.510 10 Powdery, mineral filler material 60 34.8 57 57 60 18.7 18.7 36 3418.7 Tackifier 8.7 Fibrous, mineral filler material 16 16 16 Antioxidant0.2 0.2 0.4 0.4 0.2 Stabilizer 0.1 0.1 0.1 0.1 0.1 Peel strength/peelresistance 3.4 3.1 2.1 2.6 3.5 8.9 13.1 13.6 31 15.4 [N/cm]

Said first polyisobutylene used in compositions 1 to 7 is alwaysidentical and corresponded to said especially preferred firstpolyisobutylene as defined further above. Said third polyisobutyleneused in compositions 6 and 7 corresponded to said especially preferredthird polyisobutylene as described further above. Said third butylrubber used only in the comparative compositions 1 to 5 had an averagemolecular weight M_(w) between 250,000 and 550,000. Said secondpolyisobutylene used in the composition 6 corresponded to such asfurther above defined as especially preferred. Said secondpre-crosslinked butyl rubber used in composition 7 corresponded to saidsecond partly cross-linked butyl rubber defined further above in thedescription as especially preferred. Said first depolymerized butylrubber used in the inventive compositions 8 and 9 corresponded to saidfirst depolymerized butyl rubber defined further above in thedescription as especially preferred. As a powdery, mineral fillermaterial a talcum was used, which presents a natural mixture ofmagnesium silicate hydrate and magnesium aluminium silicate hydrate in adistinct platelet structure. As a fibrous mineral filler material, awollastonit with a distinct needle structure was used. As a stabilizer,a stearic acid was used, the used antioxidant corresponded to usuallymarketable antioxidants.

In compositions

-   -   1 to 7 and 10, the average relative molar mass M _(V) (viscosity        agent) was 42,000 g/mole for the first polyisobutylene used;    -   6, 8 and 9, the average relative molar mass M _(V) (viscosity        agent) was 2,600,000 g/mole for the second polyisobutylene used;        and    -   6 to 10, the average relative molar mass (viscosity agent) was        390,000 g/mole for the third polyisobutylene used.

For the first butyl rubber used in compositions 8 and 9, the averagemolecular weight M_(w) was 36,000, the viscosity according to Brookfieldat 66° C. according to DIN EN ISO 2555:2000-01 was 1,000,000 mPa·s andthe degree of unsaturation was 3.0 mole-%.

For the second butyl rubber used in compositions 7 and 10, the Mooneyviscosity ML(1+3) at 127° C. was in a range from 80 MU to 90 MUaccording to ISO 289:2005 and the degree of unsaturation was below 1.0mole-%.

For the third butyl rubber used in compositions 1 and 5, the Mooneyviscosity ML(1+8) at 125° C. was in a range from 45 MU to 50 MUaccording to ISO 289:2005 and the degree of unsaturation was at 1.5mole-%.

The anti-corrosion compositions 1 to 10 according to the above tablewere produced in the form of a three-layered tape with one layer made ofthe mentioned compositions on a carrier foil of polyethylene, having acoupling layer on its side facing said composition. With thisthree-layered tape, a steel pipe was wrapped at a room temperature of23° C. without overlapping. Under these conditions upon determining thepeel strength/peel resistance the values as indicated in the above tableoccurred. This shows that the compositions according to the invention, 7to 10, have significantly higher values as to the peel strength/peelresistance than the compositions not corresponding to the invention, 1to 6. The compositions 7 to 10 even achieved very good cohesiveseparating images and a very good wetting of the steel.

The tests carried out show that advantageous values regarding peelstrength/peel resistance defined according to DIN 12068 in the version1999-03 can be achieved with the Anticorrosion composition according tothe invention, and even very good cohesive separating images can begenerated. Also, a good wetting of the substrate is achieved, especiallyof a steel pipe. No pre-coatings respectively primers or adhesive agentswere used. These are not necessarily required in order to fulfil thestandard according to DIN EN 12068 in the version 1999-03.

Omitting primers or adhesive agents, which is possible according to theinvention, bears the advantage that less effort has to be taken forapplying the anti-corrosion composition. Further advantageous is thatomitting the use of primers or adhesive agent, in particular suchcontaining petrol as solvent, improves environmental protection.Moreover, transporting the anticorrosion composition becomes easier, asprimers or adhesive agents containing petrol as a solvent are for safetyreasons not necessarily allowed to be transported in aircrafts.

Preferred is therefore using the anti-corrosion composition according tothe invention for the protection of pipes, systems comprising pipes aswell as other plants and/or installations from corrosion, withoutapplying primers or adhesive agents, in particular such comprisingpetrol as a solvent.

Also preferred is a method for obtaining corrosion protection on pipes,systems comprising pipes as well as other plants and/or installations byapplying the anti-corrosion composition according to the invention,which does not comprise the use of primers or adhesive agents,especially not such comprising petrol as a solvent.

The present invention provides a anti-corrosion composition which can beapplied by grouting or by spackling as well as in the form of a tape orshrink sleeve or in any other embodiment, and which has very goodadhesion properties and thus provides durable corrosion protection tothe products, systems, installations, pipes, pipelines etc. to which itis applied. Advantageously, it can, in whichever form, be used without aprimer/adhesive agent.

1. An anti-corrosion composition comprising: a first compound selectedfrom the group consisting of a first polyisobutylene having an averagerelative molar mass M _(V) ranging from about 30,000 g/mole to about100,000 g/mole and a Staudinger index J₀ ranging from about 15 cm³/g toabout 70 cm³/g and/or at least a first depolymerized butyl rubber withan apparent Brookfield viscosity at 66° C. according to DIN EN ISO2555:2000-01 ranging from about 400,000 mPa·s to about 2,000,000 mPa·sand an average molecular weight M_(W) ranging from about 20,000 to about60,000, and combinations thereof; a second compound, selected from thegroup consisting of a second polyisobutylene having an average relativemolar mass M _(V) ranging from about 900,000 g/mole to about 6,500,000g/mole and a Staudinger index J₀ ranging from about 240 cm³/g to about900 cm³/g, at least one second partly cross-linked butyl rubber with aMooney viscosity ML(1+3) at 127° C. ranging from about 65 MU to about100 MU according to ISO 289:2005, and combinations thereof; wherein theanti-corrosion composition comprises at least one first or at least onesecond polyisobutylene as well as at least one first or at least onesecond butyl rubber.
 2. An anti-corrosion composition according to claim1, wherein the first compound is present in an amount from about 20% byweight to about 66% by weight, based on the total weight of theanti-corrosion composition.
 3. An anti-corrosion composition accordingto claim 1, wherein the second compound is present in an amount fromabout 1% by weight to about 20% by weight, based on the total weight ofthe anti-corrosion composition quantity of the composition.
 4. Ananti-corrosion composition according to claim 1, further including atleast a third compound, selected from the group consisting of a thirdpolyisobutylene with a Staudinger index J₀ ranging from about 75 cm/g toabout 235 cm/g and an average relative molar mass M _(v) ranging fromabout 150,000 g/mole to about 85,000 g/mole, a third butyl rubber withan average molecular weight M_(w) ranging from about 150,000 to about2,000,000 and a Money viscosity ML(1+8) at 125° C. ranging from about 20MU to about 62 MU, measured according to ISO 289:2005, and combinationsthereof.
 5. An anti-corrosion composition according to claim 4, whereinthe third compound is present in an amount from about 10% by weight toabout 40% by weight, based on the total weight of the anti-corrosioncomposition.
 6. An anti-corrosion composition according to claim 1further including at least one filler material, at least oneantioxidant, at least one cross-linking agent, at least an elastomerand/or at least one stabilizer.
 7. An anti-corrosion compositionaccording to claim 6, wherein the at least one filler material ispresent in an amount from about 20% by weight to about 70% by weight,based on the total weight of the anti-corrosion composition.
 8. Ananti-corrosion composition according to claim 6, wherein the at leastone filler material is powdery or fibrous.
 9. An anti-corrosioncomposition according to claim 8, including one first powdery fillermaterial and one second fibrous filler material.
 10. An anti-corrosioncomposition according to claim 1 wherein the anti-corrosioncomposition-is provided in tape format or pad format.
 11. Ananti-corrosion composition according to claim 10, wherein the tape has atwo or multi-layered structure, wherein at least one layer includes theanti-corrosion composition.
 12. (canceled)
 13. A method for theprotection of products from corrosion using the anti-corrosioncomposition according to claim 1 including the steps of providing astructure to be protected and applying the composition according toclaims
 1. 14. Method according to claim 13, wherein the structure to beprotected includes pipes that are wrapped with an at leastsingle-layered tape including the anti-corrosion composition.
 15. An atleast single-layered wrapping tape comprising the composition accordingto claim 1.